Theodore Kaczynski, the alleged Unabomber, is now an infamous figure in the United States, but little is known about him.

Arrested in April 1996, Mr Kaczynski matched much of the FBI's Unabomber profile which described a middle-aged white male who was "familiar with university life," took great pride in bomb-making, and had links to Chicago and Northern California.

Ted Kaczynski was born on May 22, 1942, and grew up in Evergreen Park, a working-class suburb of Chicago.

He has the IQ of a genius. He attended Harvard University and then the University of Michigan, where he received a PhD in mathematics in 1967.

The same year, Mr Kaczynski worked as an assistant professor of mathematics at the University of California at Berkeley, where he was widely recognised as a teacher likely to get tenure. He abruptly resigned in 1969.

After his stint as a teacher, much of Ted Kaczynski's history is unclear.

Property records show that in 1971 Mr Kaczynski, along with his brother David, bought 1.4 acres of land outside of Lincoln, in western Montana. There, he lived as a recluse in a 10-by-12 foot cabin without electricity or running water.

After his arrest, neighbours reported that Kaczynski had rarely left his cabin. He rode a bicycle into the nearby of Lincoln for any food that he did not grow in his garden.